Interconnectable SENTRY Mains Smoke Alarm with Replaceable Back-Up Battery
KF21Location
Bedrooms, Living Room, Hallway/Corridor, Attic/Loft (unconverted only)Product Life
10 yearsWarranty
10‑year manufacturer’s warranty
Power
230V AC mains with battery back‑up
Back-Up Battery
1-year replaceable / 9V alkaline includedAlarm Grade
Grade D2 Specifications
| Model | |
| Power Source | |
| Sensors | |
| Audio Alarm | |
| Approvals / Certification | |
| Dimensions | |
| Weight | |
| Temperature Range | |
| Storage and Transport | |
| Humidity Range | |
| Warranty |
- Fully compatible with existing Kidde FIREX hardwired systems
- Clear 4‑SKU Sentry range across Smoke and Heat, Grade D1 and D2
- Installer‑first design supports faster fitting and cleaner replacements
- Backed by a 10‑year manufacturer’s warranty
- Supported by full launch assets including datasheets, product imagery and sell‑in materials
Product Documentation
Specifications
| Model | |
| Power Source | |
| Sensors | |
| Audio Alarm | |
| Approvals / Certification | |
| Dimensions | |
| Weight | |
| Temperature Range | |
| Storage and Transport | |
| Humidity Range | |
| Warranty |
Product Documentation
- Fully compatible with existing Kidde FIREX hardwired systems
- Clear 4‑SKU Sentry range across Smoke and Heat, Grade D1 and D2
- Installer‑first design supports faster fitting and cleaner replacements
- Backed by a 10‑year manufacturer’s warranty
- Supported by full launch assets including datasheets, product imagery and sell‑in materials
Comparison Chart
Model Number
Detection Type
Power Source
Battery Life (Minimum)
Never Change Battery
Interconnected Alarms
Voice Alerts
NCC Certified (for Motorhomes / Static Homes)
10-Year Warranty
KF21
Smoke
AC / Hard-wired
1-year (Back-up battery only)
KF21
Smoke
AC / Hard-wired
1-year (Back-up battery only)
KF20R
Smoke
AC / Hard-wired
Back-up battery only
KF20
Smoke
AC / Hard-wired
1-year (Back-up battery only)
KF21R
Smoke
AC / Hard-wired
Back-up battery only